Back in December, I switched from Scientific Atlanta 8300 DVRs to two X1 (Arris) DVR boxes. They're both DVRs, so all recorded material is viewable on either box. Years before, Comcast had installed a Commscope Amp at the service line and all devices (there are also two HD DTA boxes for smaller sets) were connected to the output of the amplifier.

The X1's were having trouble talking to each other, and the X1 boxes would lock up and had other communication issues. Comcast came and removed the amplifier, installing a six way splitter instead. Since then, I am 100% certain, the picture quality on both 4K TVs has been noticeably more grainy. The picture had looked terrific, and now, while it still looks good, is not what it had been with the amplifier. Comcast insists the amp makes no difference in picture quality. (The unused taps on the splitter have termination plugs.)

I own another Commscope amp, but am reluctant to put in back in service since the boxes had these lockup issues and Comcast (senior tech that was here) was sure the amp was what was causing these X1 DVR issues.